diff --git a/api/jhu-edu.js b/api/jhu-edu.js
index 805d0d6..a85d11d 100644
--- a/api/jhu-edu.js
+++ b/api/jhu-edu.js
@@ -1,252 +1,268 @@
-const express = require('express')
-const router = express.Router()
+const express = require("express");
+const router = express.Router();
 
-const lookup = require('country-code-lookup')
-const nestedProperty = require('nested-property')
+const lookup = require("country-code-lookup");
+const nestedProperty = require("nested-property");
 
 const column = {
-  PROVINCE_STATE: 'provincestate',
-  COUNTRY_REGION: 'countryregion',
-  LAST_UPDATE: 'lastupdate',
-  CONFIRMED: 'confirmed',
-  DEATHS: 'deaths',
-  RECOVERED: 'recovered'
-}
-
-const request = require('request')
-const csv = require('csvtojson')
+  PROVINCE_STATE: "provincestate",
+  COUNTRY_REGION: "countryregion",
+  LAST_UPDATE: "lastupdate",
+  CONFIRMED: "confirmed",
+  DEATHS: "deaths",
+  RECOVERED: "recovered",
+};
+
+const request = require("request");
+const csv = require("csvtojson");
 const csvPath = {
-  confirmed: 'https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_confirmed_global.csv',
-  deaths: 'https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_deaths_global.csv',
-  recovered: 'https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_recovered_global.csv'
-}
+  confirmed:
+    "https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_confirmed_global.csv",
+  deaths:
+    "https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_deaths_global.csv",
+  recovered:
+    "https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_recovered_global.csv",
+};
 
-const fixedCountryCodes = require('../dataset/country-codes.json')
-const iso2CountryLoc = require('../dataset/iso2-country-loc.json')
+const fixedCountryCodes = require("../dataset/country-codes.json");
+const iso2CountryLoc = require("../dataset/iso2-country-loc.json");
 
-const schedule = require('node-schedule')
-schedule.scheduleJob('42 * * * *', updateCSVDataSet) // Call every hour at 42 minutes
+const schedule = require("node-schedule");
+schedule.scheduleJob("42 * * * *", updateCSVDataSet); // Call every hour at 42 minutes
 
 const responseSet = {
-  brief: '{}',
-  latest: '{}',
-  latestOnlyCountries: '{}',
-  timeseries: '{}',
-  timeseriesOnlyCountries: '{}'
-}
-let lastUpdate
+  brief: "{}",
+  latest: "{}",
+  latestOnlyCountries: "{}",
+  timeseries: "{}",
+  timeseriesOnlyCountries: "{}",
+};
+let lastUpdate;
 
-router.get('/brief', function (req, res) {
-  res.status(200).json(responseSet.brief)
-})
+router.get("/brief", function (req, res) {
+  res.status(200).json(responseSet.brief);
+});
 
-router.get('/latest', function (req, res) {
-  const { iso2, iso3, onlyCountries } = req.query
+router.get("/latest", function (req, res) {
+  const { iso2, iso3, onlyCountries } = req.query;
 
-  let latest = onlyCountries ? responseSet.latestOnlyCountries : responseSet.latest
+  let latest = onlyCountries
+    ? responseSet.latestOnlyCountries
+    : responseSet.latest;
 
-  if (iso2) latest = filterIso2code(latest, iso2)
-  if (iso3) latest = filterIso3code(latest, iso3)
+  if (iso2) latest = filterIso2code(latest, iso2);
+  if (iso3) latest = filterIso3code(latest, iso3);
 
-  res.status(200).send(JSON.stringify(latest))
-})
+  res.status(200).json(latest);
+});
 
-router.get('/timeseries', function (req, res) {
-  const { iso2, iso3, onlyCountries } = req.query
+router.get("/timeseries", function (req, res) {
+  const { iso2, iso3, onlyCountries } = req.query;
 
-  let timeseries = onlyCountries ? responseSet.timeseriesOnlyCountries : responseSet.timeseries
+  let timeseries = onlyCountries
+    ? responseSet.timeseriesOnlyCountries
+    : responseSet.timeseries;
 
-  if (iso2) timeseries = filterIso2code(timeseries, iso2)
-  if (iso3) timeseries = filterIso3code(timeseries, iso3)
+  if (iso2) timeseries = filterIso2code(timeseries, iso2);
+  if (iso3) timeseries = filterIso3code(timeseries, iso3);
 
-  res.status(200).send(JSON.stringify(timeseries))
-})
+  res.status(200).json(timeseries);
+});
 
-function updateCSVDataSet () {
-  console.log('Updated at ' + new Date().toISOString())
+async function updateCSVDataSet() {
+  console.log("Updated at " + new Date().toISOString());
 
   const dataSource = {
     confirmed: {},
     deaths: {},
-    recovered: {}
-  }
-  lastUpdate = new Date().toISOString()
-  const queryPromise = []
-
-  Object.entries(csvPath).forEach(([category, path]) => {
-    queryPromise.push(queryCsvAndSave(dataSource, path, category))
-  })
-  Promise.all(queryPromise)
-    .then((_values) => {
-      const brief = {
-        [column.CONFIRMED]: 0,
-        [column.DEATHS]: 0,
-        [column.RECOVERED]: 0
-      }
-      const latest = {}
-      const timeseries = {}
-
-      for (const [category, value] of Object.entries(dataSource)) {
-        for (const [name, item] of Object.entries(value)) {
-          const keys = Object.keys(item)
-          const cell = item[keys[keys.length - 1]]
-          const latestCount = cell ? Number(cell) : Number(item[keys[keys.length - 2]])
-
-          // For brief
-          brief[category] += latestCount
-
-          // For latest
-          createPropertyIfNeed(latest, name, item)
-          latest[name][category] = latestCount
-
-          // For timeseries
-          createPropertyIfNeed(timeseries, name, item)
-          for (const date of keys.slice(4)) {
-            // recovered csv file uses '3/24/2020' date format instead of '3/24/20'
-            const fixedDatePropertyName = date.replace('/2020', '/20')
-
-            nestedProperty.set(timeseries[name], `timeseries.${fixedDatePropertyName}.${category}`, Number(item[date]))
-          }
+    recovered: {},
+  };
+  lastUpdate = new Date().toISOString();
+
+  try {
+    await Promise.all(
+      Object.entries(csvPath).map(([category, path]) =>
+        queryCsvAndSave(dataSource, path, category),
+      ),
+    );
+
+    const brief = {
+      [column.CONFIRMED]: 0,
+      [column.DEATHS]: 0,
+      [column.RECOVERED]: 0,
+    };
+    const latest = {};
+    const timeseries = {};
+
+    for (const [category, value] of Object.entries(dataSource)) {
+      for (const [name, item] of Object.entries(value)) {
+        const keys = Object.keys(item);
+        const cell = item[keys[keys.length - 1]];
+        const latestCount = cell
+          ? Number(cell)
+          : Number(item[keys[keys.length - 2]]);
+
+        // For brief
+        brief[category] += latestCount;
+
+        // For latest
+        createPropertyIfNeed(latest, name, item);
+        latest[name][category] = latestCount;
+
+        // For timeseries
+        createPropertyIfNeed(timeseries, name, item);
+        for (const date of keys.slice(4)) {
+          // recovered csv file uses '3/24/2020' date format instead of '3/24/20'
+          const fixedDatePropertyName = date.replace("/2020", "/20");
+
+          nestedProperty.set(
+            timeseries[name],
+            `timeseries.${fixedDatePropertyName}.${category}`,
+            Number(item[date]),
+          );
         }
       }
+    }
 
-      // Set 0 for unknown recovered value
-      for (const item of Object.values(timeseries)) {
-        for (const date of Object.values(item.timeseries)) {
-          if (!date.recovered) date.recovered = 0
-        }
+    // Set 0 for unknown recovered value
+    for (const item of Object.values(timeseries)) {
+      for (const date of Object.values(item.timeseries)) {
+        if (!date.recovered) date.recovered = 0;
       }
+    }
 
-      responseSet.brief = brief
-      responseSet.latest = Object.values(latest)
-      responseSet.timeseries = Object.values(timeseries)
-
-      // Uses deep copy
-      // https://stackoverflow.com/a/122704/3614334
-      const copyLatest = JSON.parse(JSON.stringify(latest))
-      responseSet.latestOnlyCountries = getMergedByCountry(Object.values(copyLatest))
-      const copyTimeseries = JSON.parse(JSON.stringify(timeseries))
-      responseSet.timeseriesOnlyCountries = getMergedByCountry(Object.values(copyTimeseries))
-
-      console.log(`Confirmed: ${brief.confirmed}, Deaths: ${brief.deaths}, Recovered: ${brief.recovered}`)
-    })
-    .catch((error) => {
-      console.log('Error on queryPromise: ' + error)
-    })
+    responseSet.brief = brief;
+    responseSet.latest = Object.values(latest);
+    responseSet.timeseries = Object.values(timeseries);
+
+    // Uses deep copy
+    // https://stackoverflow.com/a/122704/3614334
+    const copyLatest = JSON.parse(JSON.stringify(latest));
+    responseSet.latestOnlyCountries = getMergedByCountry(
+      Object.values(copyLatest),
+    );
+    const copyTimeseries = JSON.parse(JSON.stringify(timeseries));
+    responseSet.timeseriesOnlyCountries = getMergedByCountry(
+      Object.values(copyTimeseries),
+    );
+
+    console.log(
+      `Confirmed: ${brief.confirmed}, Deaths: ${brief.deaths}, Recovered: ${brief.recovered}`,
+    );
+  } catch (error) {
+    console.log("Error on queryPromise: " + error);
+  }
 }
 
-function getMergedByCountry (list) {
-  const mergedList = { }
+function getMergedByCountry(list) {
+  const mergedList = {};
 
   for (const item of list) {
-    const countryName = item.countryregion
+    const countryName = item.countryregion;
 
     if (mergedList[countryName]) {
-      const country = mergedList[countryName]
+      const country = mergedList[countryName];
 
       // for latest api
-      mergeConfirmDeathRecover(country, item)
+      mergeConfirmDeathRecover(country, item);
 
       // for timeseries api
       if (item.timeseries) {
-        const timeseries = item.timeseries
-        const mergedTimeseries = country.timeseries
+        const timeseries = item.timeseries;
+        const mergedTimeseries = country.timeseries;
 
         for (const key of Object.keys(timeseries)) {
-          mergeConfirmDeathRecover(mergedTimeseries[key], timeseries[key])
+          mergeConfirmDeathRecover(mergedTimeseries[key], timeseries[key]);
         }
       }
 
       // Overwrite location
       if (item.countrycode) {
-        const iso2 = item.countrycode.iso2
-        country.location = iso2CountryLoc[iso2]
+        const iso2 = item.countrycode.iso2;
+        country.location = iso2CountryLoc[iso2];
       }
     } else {
-      delete item.provincestate
-      mergedList[countryName] = item
+      delete item.provincestate;
+      mergedList[countryName] = item;
     }
   }
 
-  return Object.values(mergedList)
+  return Object.values(mergedList);
 }
 
-function mergeConfirmDeathRecover (target, item) {
-  if (!(target && item)) return
+function mergeConfirmDeathRecover(target, item) {
+  if (!(target && item)) return;
 
-  if (item.confirmed) merge(target, item, 'confirmed')
-  if (item.deaths) merge(target, item, 'deaths')
-  if (item.recovered) merge(target, item, 'recovered')
+  if (item.confirmed) merge(target, item, "confirmed");
+  if (item.deaths) merge(target, item, "deaths");
+  if (item.recovered) merge(target, item, "recovered");
 }
 
-function merge (target, item, key) {
-  const cur = target[key] ? target[key] : 0
-  const add = item[key] ? item[key] : 0
+function merge(target, item, key) {
+  const cur = target[key] ? target[key] : 0;
+  const add = item[key] ? item[key] : 0;
 
-  target[key] = cur + add
+  target[key] = cur + add;
 }
 
-function filterIso2code (source, code) {
-  return source.filter(item => {
-    const countryCode = item.countrycode ? item.countrycode.iso2 : 'unknown'
-    return countryCode === code
-  })
+function filterIso2code(source, code) {
+  return source.filter((item) => {
+    const countryCode = item.countrycode ? item.countrycode.iso2 : "unknown";
+    return countryCode === code;
+  });
 }
 
-function filterIso3code (source, code) {
-  return source.filter(item => {
-    const countryCode = item.countrycode ? item.countrycode.iso3 : 'unknown'
-    return countryCode === code
-  })
+function filterIso3code(source, code) {
+  return source.filter((item) => {
+    const countryCode = item.countrycode ? item.countrycode.iso3 : "unknown";
+    return countryCode === code;
+  });
 }
 
-function queryCsvAndSave (dataSource, path, category) {
+function queryCsvAndSave(dataSource, path, category) {
   return csv()
     .fromStream(request.get(path))
     .subscribe((json) => {
-      if (json['Province/State']) {
-        const provincestate = json['Province/State']
-        dataSource[category][provincestate] = json
-      } else if (json['Country/Region']) {
-        const countryregion = json['Country/Region']
-        dataSource[category][countryregion] = json
+      if (json["Province/State"]) {
+        const provincestate = json["Province/State"];
+        dataSource[category][provincestate] = json;
+      } else if (json["Country/Region"]) {
+        const countryregion = json["Country/Region"];
+        dataSource[category][countryregion] = json;
       }
 
       return new Promise((resolve, reject) => {
-        resolve()
-      })
-    })
+        resolve();
+      });
+    });
 }
 
-function createPropertyIfNeed (target, name, item) {
+function createPropertyIfNeed(target, name, item) {
   if (!nestedProperty.has(target, name)) {
     target[name] = {
-      [column.PROVINCE_STATE]: item['Province/State'],
-      [column.COUNTRY_REGION]: item['Country/Region'],
+      [column.PROVINCE_STATE]: item["Province/State"],
+      [column.COUNTRY_REGION]: item["Country/Region"],
       [column.LAST_UPDATE]: lastUpdate,
       location: {
         lat: Number(item.Lat),
-        lng: Number(item.Long)
-      }
-    }
+        lng: Number(item.Long),
+      },
+    };
 
     // Append country codes
-    const countryName = item['Country/Region']
-    if (lookup.byCountry(countryName)) {
-      appendCountryCode(lookup.byCountry(countryName))
-    } else if (fixedCountryCodes[countryName]) {
-      appendCountryCode(lookup.byCountry(fixedCountryCodes[countryName]))
-    }
-  }
-
-  function appendCountryCode (countryCode) {
-    target[name].countrycode = {
-      iso2: countryCode.iso2,
-      iso3: countryCode.iso3
+    const countryName = item["Country/Region"];
+    const countryCode =
+      lookup.byCountry(countryName) ||
+      lookup.byCountry(fixedCountryCodes[countryName]);
+    if (countryCode) {
+      target[name].countrycode = {
+        iso2: countryCode.iso2,
+        iso3: countryCode.iso3,
+      };
     }
   }
 }
 
-updateCSVDataSet()
+updateCSVDataSet();
 
-module.exports = router
+module.exports = router;
diff --git a/api/korea-kcdc.js b/api/korea-kcdc.js
index 2cd1ca8..e789db9 100644
--- a/api/korea-kcdc.js
+++ b/api/korea-kcdc.js
@@ -1,48 +1,51 @@
-const express = require('express')
-const router = express.Router()
+const express = require("express");
+const router = express.Router();
 
-const fetch = require('node-fetch')
-const fs = require('fs')
-const url = 'https://raw.githubusercontent.com/LiveCoronaDetector/livecod/master/data/koreaRegionalData.js'
-const tempFilePath = './dataset/temp-kcdc.js'
-const tempModulePath = '../dataset/temp-kcdc.js'
-const exportModule = 'module.exports = koreaRegionalData;'
+const fetch = require("node-fetch");
+const fs = require("fs");
+const path = require("path");
+const schedule = require("node-schedule");
 
-const schedule = require('node-schedule')
-schedule.scheduleJob('12 * * * *', updateDataSet) // Call every hour at 12 minutes
+const url =
+  "https://raw.githubusercontent.com/LiveCoronaDetector/livecod/master/data/koreaRegionalData.js";
+const tempFilePath = path.join(__dirname, "../dataset/temp-kcdc.js");
+const exportModule = "module.exports = koreaRegionalData;";
 
-let koreaRegionalData = {}
+let koreaRegionalData = {};
 
-router.get('/brief', function (req, res) {
-  res.status(200).json(koreaRegionalData)
-})
+router.get("/brief", (req, res) => {
+  res.status(200).json(koreaRegionalData);
+});
 
-async function updateDataSet () {
-  console.log('Korea KCDC Updated at ' + new Date().toISOString())
+const updateDataSet = async () => {
+  console.log(`Korea KCDC Updated at ${new Date().toISOString()}`);
 
   try {
-    const response = await fetch(url)
-    const body = await response.text()
+    const response = await fetch(url);
+    const body = await response.text();
 
-    fs.writeFile(tempFilePath, body + exportModule, function (err) {
+    fs.writeFile(tempFilePath, `${body}${exportModule}`, (err) => {
       if (err) {
-        console.error(err)
-      } else {
-        try {
-          koreaRegionalData = require(tempModulePath)
-          console.log('Korea KCDC data was saved!')
-        } catch (e) {
-          console.error(e)
-          koreaRegionalData = {}
-        }
+        console.error(err);
+        return;
       }
-    })
+
+      try {
+        delete require.cache[require.resolve(tempFilePath)];
+        koreaRegionalData = require(tempFilePath);
+        console.log("Korea KCDC data was saved!");
+      } catch (e) {
+        console.error(e);
+        koreaRegionalData = {};
+      }
+    });
   } catch (e) {
-    console.error(e)
-    koreaRegionalData = {}
+    console.error(e);
+    koreaRegionalData = {};
   }
-}
+};
 
-updateDataSet()
+schedule.scheduleJob("12 * * * *", updateDataSet); // Call every hour at 12 minutes
+updateDataSet();
 
-module.exports = router
+module.exports = router;